[R] change plotting symbol for groups in trellis graph

Hi, how can I change the plotting symbol for the groups in a trellis panel dotplot. My graph is similar to: library(trellis) dotplot(variety ~ yield | site, data = barley, groups = year, key = simpleKey(levels(barley$year), space = right), xlab = Barley Yield

[R] as.data.frame(cbind()) transforming numeric to factor?

Dear List, why does as.data.frame(cbind()) transform numeric variables to factors, once one of the other variablesused is a character vector? # x.1 - rnorm(10) x.2 - c(rep(Test,10)) Foo - as.data.frame(cbind(x.1)) is.factor(Foo$x.1) Foo - as.data.frame(cbind(x.1,x.2)) is.factor(Foo$x.1) # I

Re: [R] as.data.frame(cbind()) transforming numeric to factor?

Thanks everybody. I recognize my mistake now. I think as.data.frame(cbind(x.1,x.2),stringsAsFactors = FALSE) would be a good idea. Tom On 8/18/06, Prof Brian Ripley [EMAIL PROTECTED] wrote: On Fri, 18 Aug 2006, Tom Boonen wrote: Dear List, why does as.data.frame(cbind()) transform

[R] ARMA(1,1) for panel data

Dear List, I am new to TS-Modeling in R. I would like to fit an ARMA(1,1) model for a balanced panel, running Y on a full set of unit and year dummies using an arma(1,1) for the disturbance: y_it=unit.dummies+yeardummies+e_it where: e_it=d*e_it-1+u_it+q*u_it-1 How can I fit this model in R?